<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<body>
    <script>
        //提取数字
        const str = `
        <ul>
            <ol>
                <a>monday</a>
                <p>3.15</p>
            </ol>
            <ol>
                <a>tuesday</a>
                <p>3.16</p>
            </ol>
            <ol>
                <a>wednesday</a>
                <p>3.17</p>
            </ol>
        </ul>`
        const req = /<ol>.*?<a>(.*?)<\/a>.*?<p>(.*?)<\/p>.*?<\/ol>/gs
        const res = str.matchAll(req)
        //console.log([...res])
        for (let v of res){
            console.log(v)
        }
    </script>
</body>
</html>